Achieving Zero/Negative-Emissions Coal-Fired Power Plants Using Amine-Based Postcombustion CO2 Capture Technology and Biomass Cocombustion

The strengthening carbon mitigation efforts to meet the 1.5 degrees C target requires the development of zero/negative CO2 emission technologies to eliminate large direct CO2 emissions from fossil-fuel fired power stations. Amine scrubbing is a dominant technology to capture CO2 from fossil-fuel power stations, but its application in achieving zero/negative emission in power stations is rarely reported. The present study investigates the MEA-based technologies to achieve zero and negative CO2 emission in coal-fired power stations, and their techno-economic performance was evaluated in detail. These zero/negative-emission technologies include 99.7% CO2 capture from flue gas (zero emission), biomass cocombustion with coal integrated with CO2 capture at ratios of 10% biomass/90% CO2 capture and 5% biomass/95% CO2 capture (zero-emission), and 10% biomass/95% CO2 capture for negative-emission power station. Our investigation revealed that these zero/negative-emission technologies are technically and economically viable, and their CO2 avoided costs did not significantly increase compared to the standard 90% CO2 capture. The CO2 avoided cost for 99.7%-capture is estimated at $66.5/tonne CO2 which is $2.6/tonne CO2 higher than that of 90% capture. The biomass cocombustion zero/negative-emission technologies show better economic performance with CO2 avoided cost of $64.1-64.8/tonne CO2, which is only $0.2-0.7/tonne CO2 higher than the standard 90%-capture. These results indicate that the amine-based CO2 capture integrated with biomass cocombustion technology would be economically competitive to achieve zero or even negative CO2 emissions in coal-fired power stations.